diff --git a/ueforth/common/forth_namespace_tests.fs b/ueforth/common/forth_namespace_tests.fs
index 3cc5923..44d31e2 100644
--- a/ueforth/common/forth_namespace_tests.fs
+++ b/ueforth/common/forth_namespace_tests.fs
@@ -272,21 +272,23 @@ e: check-float-opcodes
 ;e
 
 e: check-files
-  out: file-size 
-  out: resize-file 
-  out: reposition-file 
-  out: file-position 
-  out: write-file 
-  out: read-file 
-  out: rename-file 
-  out: delete-file 
-  out: flush-file 
-  out: close-file 
-  out: create-file 
-  out: open-file 
-  out: r/w 
-  out: w/o 
-  out: r/o 
+  out: NON-BLOCK 
+  out: FILE-SIZE 
+  out: RESIZE-FILE 
+  out: REPOSITION-FILE 
+  out: FILE-POSITION 
+  out: READ-FILE 
+  out: WRITE-FILE 
+  out: RENAME-FILE 
+  out: DELETE-FILE 
+  out: CREATE-FILE 
+  out: OPEN-FILE 
+  out: FLUSH-FILE 
+  out: CLOSE-FILE 
+  out: BIN 
+  out: R/W 
+  out: W/O 
+  out: R/O 
 ;e
 
 e: check-blocks
@@ -476,7 +478,6 @@ e: test-posix-forth-namespace
   out: #! 
   out: ms-ticks 
   out: ms 
-  out: non-block 
   check-files
   out: default-key 
   out: default-type 
@@ -541,22 +542,7 @@ e: check-esp32-basics2
   out: setsockopt 
   out: MDNS.begin 
   out: dacWrite 
-  out: NON-BLOCK 
-  out: FILE-SIZE 
-  out: RESIZE-FILE 
-  out: REPOSITION-FILE 
-  out: FILE-POSITION 
-  out: READ-FILE 
-  out: WRITE-FILE 
-  out: DELETE-FILE 
-  out: CREATE-FILE 
-  out: OPEN-FILE 
-  out: FLUSH-FILE 
-  out: CLOSE-FILE 
-  out: BIN 
-  out: W/O 
-  out: R/W 
-  out: R/O 
+  check-files
   out: TERMINATE 
   out: MS-TICKS 
   out: pulseIn 
diff --git a/ueforth/esp32/builtins.h b/ueforth/esp32/builtins.h
index 0fae2af..ae41d50 100644
--- a/ueforth/esp32/builtins.h
+++ b/ueforth/esp32/builtins.h
@@ -93,8 +93,8 @@ static cell_t ResizeFile(cell_t fd, cell_t size);
 
 #define REQUIRED_FILES_SUPPORT \
   X("R/O", R_O, PUSH O_RDONLY) \
-  X("R/W", R_W, PUSH O_RDWR) \
   X("W/O", W_O, PUSH O_WRONLY) \
+  X("R/W", R_W, PUSH O_RDWR) \
   Y(BIN, ) \
   X("CLOSE-FILE", CLOSE_FILE, tos = close(tos); tos = tos ? errno : 0) \
   X("FLUSH-FILE", FLUSH_FILE, fsync(tos); /* fsync has no impl and returns ENOSYS :-( */ tos = 0) \
@@ -107,6 +107,7 @@ static cell_t ResizeFile(cell_t fd, cell_t size);
   X("DELETE-FILE", DELETE_FILE, cell_t len = n0; DROP; \
     memcpy(filename, a0, len); filename[len] = 0; \
     n0 = unlink(filename); n0 = n0 ? errno : 0) \
+  X("RENAME-FILE", RENAME_FILE, NIPn(3); /* unimplemented */ n0 = 1) \
   X("WRITE-FILE", WRITE_FILE, cell_t fd = n0; DROP; cell_t len = n0; DROP; \
     n0 = write(fd, a0, len); n0 = n0 != len ? errno : 0) \
   X("READ-FILE", READ_FILE, cell_t fd = n0; DROP; cell_t len = n0; DROP; \
diff --git a/ueforth/posix/posix.fs b/ueforth/posix/posix.fs
index 5bbe5bb..5bfc1a2 100644
--- a/ueforth/posix/posix.fs
+++ b/ueforth/posix/posix.fs
@@ -156,29 +156,29 @@ z" fcntl" 3 sysfunc fcntl
 forth definitions posix
 
 ( Generic Files )
-O_RDONLY constant r/o
-O_WRONLY constant w/o
-O_RDWR constant r/w
+O_RDONLY constant R/O
+O_WRONLY constant W/O
+O_RDWR constant R/W
+: BIN ( fh -- fh ) ;
 
-: open-file ( a n fam -- fh ior ) >r s>z r> 0777 open sign-extend d0<ior ;
-: create-file ( a n fam -- fh ior )
+: CLOSE-FILE ( fh -- ior ) close sign-extend ;
+: FLUSH-FILE ( fh -- ior ) fsync sign-extend ;
+: OPEN-FILE ( a n fam -- fh ior ) >r s>z r> 0777 open sign-extend d0<ior ;
+: CREATE-FILE ( a n fam -- fh ior )
    >r s>z r> O_CREAT or 0777 open sign-extend d0<ior ;
-: close-file ( fh -- ior ) close sign-extend ;
-: flush-file ( fh -- ior ) fsync sign-extend ;
-: delete-file ( a n -- ior ) s>z unlink sign-extend ;
-: rename-file ( a n a n -- ior ) s>z -rot s>z swap rename sign-extend ;
-: read-file ( a n fh -- n ior ) -rot read d0<ior ;
-: write-file ( a n fh -- ior ) -rot dup >r write r> = 0= ;
-: file-position ( fh -- n ior ) 0 SEEK_CUR lseek d0<ior ;
-: reposition-file ( n fh -- ior ) swap SEEK_SET lseek 0< ;
-: resize-file ( n fh -- ior ) swap ftruncate 0< ;
-: file-size ( fh -- n ior )
+: DELETE-FILE ( a n -- ior ) s>z unlink sign-extend ;
+: RENAME-FILE ( a n a n -- ior ) s>z -rot s>z swap rename sign-extend ;
+: WRITE-FILE ( a n fh -- ior ) -rot dup >r write r> = 0= ;
+: READ-FILE ( a n fh -- n ior ) -rot read d0<ior ;
+: FILE-POSITION ( fh -- n ior ) 0 SEEK_CUR lseek d0<ior ;
+: REPOSITION-FILE ( n fh -- ior ) swap SEEK_SET lseek 0< ;
+: RESIZE-FILE ( n fh -- ior ) swap ftruncate 0< ;
+: FILE-SIZE ( fh -- n ior )
    dup 0 SEEK_CUR lseek >r
    dup 0 SEEK_END lseek r> swap >r
          SEEK_SET lseek drop r> d0<ior ;
-
 ( Non-standard )
-: non-block ( fh -- ior ) F_SETFL FNDELAY fcntl ;
+: NON-BLOCK ( fh -- ior ) F_SETFL FNDELAY fcntl ;
 
 ( Other Utils )
 : ms ( n -- ) 1000 * usleep drop ;
diff --git a/ueforth/windows/windows.fs b/ueforth/windows/windows.fs
index 6bb7107..7c5ee1c 100644
--- a/ueforth/windows/windows.fs
+++ b/ueforth/windows/windows.fs
@@ -149,33 +149,35 @@ $80 constant FILE_ATTRIBUTE_NORMAL
 forth definitions windows
 
 ( Generic Files )
-$80000000 constant r/o  ( GENERIC_READ )
-$40000000 constant w/o  ( GENERIC_WRITE )
-r/o w/o or constant r/w
-: open-file ( a n fam -- fh ior )
+$80000000 constant R/O ( GENERIC_READ )
+$40000000 constant W/O  ( GENERIC_WRITE )
+R/O W/O or constant R/W
+: BIN ( fh -- fh ) ;
+: CLOSE-FILE ( fh -- ior ) CloseHandle 0=ior ;
+: FLUSH-FILE ( fh -- ior ) FlushFileBuffers 0=ior ;
+: OPEN-FILE ( a n fam -- fh ior )
    >r s>z r> FILE_SHARE_READ FILE_SHARE_WRITE or NULL
    OPEN_EXISTING FILE_ATTRIBUTE_NORMAL NULL CreateFileA d0<ior ;
-: create-file ( a n fam -- fh ior )
+: CREATE-FILE ( a n fam -- fh ior )
    >r s>z r> FILE_SHARE_READ FILE_SHARE_WRITE or NULL
    CREATE_ALWAYS FILE_ATTRIBUTE_NORMAL NULL CreateFileA d0<ior ;
-: close-file ( fh -- ior ) CloseHandle 0=ior ;
-: flush-file ( fh -- ior ) FlushFileBuffers 0=ior ;
-: delete-file ( a n -- ior ) s>z DeleteFileA 0=ior ;
-: rename-file ( a n a n -- ior ) s>z -rot s>z swap MoveFileA 0=ior ;
-: read-file ( a n fh -- n ior ) -rot 0 >r rp@ NULL ReadFile r> swap 0=ior ;
-: write-file ( a n fh -- ior )
+: DELETE-FILE ( a n -- ior ) s>z DeleteFileA 0=ior ;
+: RENAME-FILE ( a n a n -- ior ) s>z -rot s>z swap MoveFileA 0=ior ;
+: WRITE-FILE ( a n fh -- ior )
    -rot dup >r 0 >r rp@ NULL WriteFile
    if r> r> <> else rdrop rdrop GetLastError then ;
-: file-position ( fh -- n ior )
+: READ-FILE ( a n fh -- n ior ) -rot 0 >r rp@ NULL ReadFile r> swap 0=ior ;
+: FILE-POSITION ( fh -- n ior )
    0 NULL FILE_CURRENT SetFilePointer dup invalid?ior ;
-: reposition-file ( n fh -- ior )
+: REPOSITION-FILE ( n fh -- ior )
    swap NULL FILE_BEGIN SetFilePointer invalid?ior ;
-: resize-file ( n fh -- ior )
+: RESIZE-FILE ( n fh -- ior )
    dup file-position dup if drop 2drop 1 ior exit else drop then >r
    dup -rot reposition-file if rdrop drop 1 ior exit then
    dup SetEndOfFile 0= if rdrop drop 1 ior exit then
    r> swap reposition-file ;
-: file-size ( fh -- n ior ) NULL GetFileSize dup invalid?ior ;
+: FILE-SIZE ( fh -- n ior ) NULL GetFileSize dup invalid?ior ;
+: NON-BLOCK ( fh -- ior ) 1 throw ;  ( IMPLEMENT! )
 
 ( Other Utils )
 : ms ( n -- ) Sleep ;